1. Technical Field
The present invention relates to a piezoelectric device, a piezoelectric actuator, a liquid ejecting head, and a liquid ejecting apparatus.
2. Related Art
For example, a piezoelectric device in which a crystallized ceramic material is disposed between two electrodes is utilized as a piezoelectric actuator. An example of the piezoelectric actuator includes a type in which a movable member such as a vibrating plate is actuated in a bending vibration mode. Such a piezoelectric actuator is utilized in an ink jet recording head, in which a pressure generating chamber that is in communication with a nozzle hole that ejects an ink liquid is partially formed with a vibrating plate and in which the vibrating plate is actuated by a piezoelectric device to pressurize ink that has been introduced into the pressure generating chamber with the result that the ink liquid is ejected from the nozzle hole.
On the other hand, the configuration in which the crystallized ceramic material is disposed between the two electrodes is also utilized in a ferroelectric memory or the like other than the above piezoelectric device. For example, in JP-A-2007-043166, a ferroelectric structure is proposed, in which a ferroelectric layer is disposed between a lower electrode and an upper electrode.
For example, in order to preclude a change in shape and a chemical change due to heat applied during sintering of a piezoelectric layer formed with a ceramic, platinum group metals such as Ru, Rh, Pd, Os, Ir, and Pt are commonly used as materials of typical piezoelectric devices.
Such metals have advantages such as relatively high electrical conductivity and chemical stability but have a disadvantage such as relatively high rigidity, resulting in such metals being fragile. Accordingly, in existing piezoelectric devices, because the electrode of the piezoelectric device contains such platinum group metals, the rigidity of the electrode may be increased to restrict the change in the shape of the piezoelectric device, or the friability of the electrode may cause destruction of the electrode and piezoelectric layer. Furthermore, such metals are expensive nowadays, resulting in high production costs of piezoelectric devices.